package com.gxd.commons.codec;

import org.apache.commons.codec.DecoderException;
import org.apache.commons.codec.binary.Base64;
import org.apache.commons.codec.binary.Hex;
import org.apache.commons.text.StringEscapeUtils;

import java.io.UnsupportedEncodingException;
import java.net.URLDecoder;
import java.net.URLEncoder;

/**
 * @Author:gxd
 * @Description:封装各种格式的编码解码工具类<br>
 * 1.Commons-Codec的 hex/base64 编码 <br>
 * 2.自制的base62 编码 <br>
 * 3.Commons-Lang的xml/html escape <br>
 * 4.JDK提供的URLEncoder
 * @Date: 11:42 2017/12/27
 */
public class EncodeUtils {

    private static final String DEFAULT_URL_ENCODING = "UTF-8";
    private static final char[] BASE62 = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz".toCharArray();

    /**
     * Hex编码.
     * @param input
     * @return
     */
    public static String hexEncodeString(String input) {
        return hexEncodeString(input, DEFAULT_URL_ENCODING);
    }

    /**
     * Hex编码.
     */
    public static String hexEncodeString(String input, String charset) {
        try {
            if (input == null) {
                return "";
            }
            return hexEncode(input.getBytes(charset));
        } catch (UnsupportedEncodingException e) {
            throw new IllegalStateException("Hex string encode exception", e);
        }
    }

    /**
     * Hex编码.
     */
    public static String hexEncode(byte[] input) {
        return Hex.encodeHexString(input);
    }

    /**
     * Hex解码.
     */
    public static String hexDecodeString(String input) {
        return hexDecodeString(input, DEFAULT_URL_ENCODING);
    }

    /**
     * Hex解码.
     */
    public static String hexDecodeString(String input, String charset) {
        try {
            return new String(hexDecode(input), charset);
        } catch (UnsupportedEncodingException e) {
            throw new IllegalStateException("Hex string encode exception", e);
        }
    }

    /**
     * Hex解码.
     */
    public static byte[] hexDecode(String input) {
        try {
            return Hex.decodeHex(input.toCharArray());
        } catch (DecoderException e) {
            throw new IllegalStateException("Hex Decoder exception", e);
        }
    }

    /**
     * Base64编码.
     */
    public static String base64Encode(byte[] input) {
        return new String(Base64.encodeBase64(input));
    }

    /**
     * Base64编码, URL安全(将Base64中的URL非法字符如+,/=转为其他字符, 见RFC3548).
     */
    public static String base64UrlSafeEncode(byte[] input) {
        return Base64.encodeBase64URLSafeString(input);
    }

    /**
     * Base64解码.
     */
    public static byte[] base64Decode(String input) {
        return Base64.decodeBase64(input);
    }


    /**
     * URL 编码.
     */
    public static String urlEncode(String input, String encoding) {
        if (input == null) {
            return null;
        }
        try {
            String str = URLEncoder.encode(input, encoding);
            return str.replaceAll("\\+", "%20"); // 空格被替换成+,js是%20,所以此处将+替换成%20
        } catch (UnsupportedEncodingException e) {
            throw new IllegalArgumentException(
                    "Unsupported Encoding Exception", e);
        }
    }


    /**
     * URL 解码.
     */
    public static String urlDecode(String input, String encoding) {
        if (input == null) {
            return null;
        }
        try {
            return URLDecoder.decode(input, encoding);
        } catch (UnsupportedEncodingException e) {
            throw new IllegalArgumentException(
                    "Unsupported Encoding Exception", e);
        }
    }

    /**
     * Hex编码.
     */
    public static String encodeHex(byte[] input) {
        return Hex.encodeHexString(input);
    }

    /**
     * Hex解码.
     */
    public static byte[] decodeHex(String input) {
        try {
            return Hex.decodeHex(input.toCharArray());
        } catch (DecoderException e) {
            throw new RuntimeException(e);
        }
    }

    /**
     * Base64编码.
     */
    public static String encodeBase64(byte[] input) {
        return Base64.encodeBase64String(input);
    }

    /**
     * Base64编码, URL安全(将Base64中的URL非法字符'+'和'/'转为'-'和'_', 见RFC3548).
     */
    public static String encodeUrlSafeBase64(byte[] input) {
        return Base64.encodeBase64URLSafeString(input);
    }

    /**
     * Base64解码.
     */
    public static byte[] decodeBase64(String input) {
        return Base64.decodeBase64(input);
    }

    /**
     * Base62编码。
     */
    public static String encodeBase62(byte[] input) {
        char[] chars = new char[input.length];
        for (int i = 0; i < input.length; i++) {
            chars[i] = BASE62[((input[i] & 0xFF) % BASE62.length)];
        }
        return new String(chars);
    }

    /**
     * Html 转码.
     */
    public static String escapeHtml(String html) {
        return StringEscapeUtils.escapeHtml4(html);
    }

    /**
     * Html 解码.
     */
    public static String unescapeHtml(String htmlEscaped) {
        return StringEscapeUtils.unescapeHtml4(htmlEscaped);
    }

    /**
     * Xml 转码.
     */
    @SuppressWarnings("deprecation")
    public static String escapeXml(String xml) {
        return StringEscapeUtils.escapeXml11(xml);
    }

    /**
     * Xml 解码.
     */
    public static String unescapeXml(String xmlEscaped) {
        return StringEscapeUtils.unescapeXml(xmlEscaped);
    }

    /**
     * URL 编码, Encode默认为UTF-8.
     */
    public static String urlEncode(String part) {
        try {
            return URLEncoder.encode(part, DEFAULT_URL_ENCODING);
        } catch (UnsupportedEncodingException e) {
           throw new RuntimeException(e);
        }
    }

    /**
     * URL 解码, Encode默认为UTF-8.
     */
    public static String urlDecode(String part) {
        try {
            return URLDecoder.decode(part, DEFAULT_URL_ENCODING);
        } catch (UnsupportedEncodingException e) {
            throw new RuntimeException(e);
        }
    }
}
